Small Business Server Storage Capacity and Redundancy

The primary purpose of any server—NAS or application—is to store, share, and protect files. That makes the amount of storage capacity and type of redundancy it offers major considerations. Any respectable small business server uses at least two hard drives configured via RAID (levels 1, 10, 5 to ensure against data loss. Many servers offer four drives, sometimes six, and some NAS vendors split the difference and offer five drives on certain models.

Obviously, the greater the number of drives a small business server supports, the more storage capacity will provide. SATA drives currently max out at 4 TB; so in a four-drive server, that translates into a maximum capacity of 16 TB. But it’s not quite that simple, because you don’t actually get to use it all that storage in a RAID setup. (In RAID 0 you do, but it’s a terrible choice for a server because it not only doesn’t provide any redundancy; it actually leaves your data more vulnerable than if it were on a single disk.)

When determining how much usable storage a server will yield, bear in mind that with RAID 1 you’ll lose 50 percent of the raw storage capacity, because the contents of each drive is mirrored to another identical drive. RAID 10 works much the same way, except that it mirrors pairs of drives rather than single ones. Ergo, RAID 1 is the only option for two-drive servers, while RAID 10 is more appropriate for those with four drives.

RAID 5, which requires a minimum of three drives, uses 1/x of the total capacity (where x is the number of drives) to store its redundancy data across all drives. Therefore, RAID 5 costs you 33 percent of your total storage capacity with three drives (1/3) or 25 percent with four (1/4).

As you can see, RAID 5 provides more cost-effective data protection. But it also takes longer to recover from a drive failure, since the replacement drive must be rebuilt using data stored on the remaining drives (and during this process, server performance will suffer).

Most, but not all, servers support hot-plugging. In the event of a drive failure, hot-plugging lets you remove and replace drives without having to shut down the server first. This is important if you can’t afford even a few minutes of down time during the business day.

Determining how much storage your server will need can be a challenge, but a business that deals with videos and high resolution photos will naturally eat through storage a lot faster than one that deals primarily in smaller file types such as documents and spreadsheets. Note: always overestimate your storage needs to the extent that your budget permits. This allows for future growth.

As a general rule, a smaller number of larger drives, while more expensive, makes future expansion easier. In a four drive-capable server configured with RAID 5, for example, four 2 TB drives and three 3 TB drives give you same 6TB of usable storage, but the latter configuration gives you the option to add a fourth 3 TB drive later and easily bump your capacity up to 9 TB.

Small Business Server: Remote Access and Management

Just because you’ve chosen an on-premises server rather than hosting your files in the cloud doesn’t mean you have to sacrifice accessing your data from outside of the office. Just about any server will provide some form of remote access, but capabilities and user-friendliness can vary considerably. Unfortunately, comparing remote access features between servers isn’t quite as straightforward as comparing more concrete specs such as storage capacity, so pay extra attention to how a server handles remote access if it will be an important requirement for your small business.

One question to ask is whether a server requires an intermediary (run either by the equipment vendor or a third-party) to facilitate remote access. Such services can make remote access work through a firewall with little-to-no configuration effort, but they also leave you at the mercy of that service (if it’s down, so is access to your data). Also, is the service free or does it carry an additional monthly or annual charge?

Remote access to server files via a Web browser is the minimum standard, but clunky interfaces can often make this option less than ideal for working on the road (especially if you frequently work with multiple files, or create and edit files more often than simply reading them). Alternative remote access options can provide better integration with remote employees’ PCs or mobile devices.

One good example is the Personal Cloud feature (PDF link) found on LenovoEMC NAS devices (including the aforementioned px2-300d). Another is the Remote Web Access feature of Windows Server 2012 Essentials R2 (as found on the WD Sentinel DS6100, among others) which has a touch-optimized UI for access from smartphones and tablets and offers users not just remote access to files and folders, but remote control of PCs.

So there you have it. When considering adding a server to your small business, answer the following questions:

Do I need this server to run applications, or just to store data?

Does this server have ample and/or easily expandable storage capacity?

Does this server make remote access to data simple or cumbersome?

Armed with the answers to these questions, you'll choose a server that will help your business as it grows for years to come.